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CTYPE(3)                   Library Functions Manual                   CTYPE(3)



NAME
       isalpha, isupper, islower, isdigit, isalnum, isspace, ispunct, isprint,
       iscntrl, isascii - character classification macros

SYNOPSIS
       #include <&lt;ctype.h>&gt;

       isalpha(c)

       . . .

DESCRIPTION
       These macros classify ASCII-coded integer values by table lookup.  Each
       is  a predicate returning nonzero for true, zero for false.  Isascii is
       defined on all integer values; the rest are defined only where  isascii
       is true and on the single non-ASCII value EOF (see stdio(3S)).

       isalpha        c is a letter

       isupper        c is an upper case letter

       islower        c is a lower case letter

       isdigit        c is a digit

       isalnum        c is an alphanumeric character

       isspace        c is a space, tab, carriage return, newline, or formfeed

       ispunct        c  is  a  punctuation  character  (neither  control  nor
                      alphanumeric)

       isprint        c is a printing character, code 040(8)  (space)  through
                      0176 (tilde)

       iscntrl        c is a delete character (0177) or ordinary control char-
                      acter (less than 040).

       isascii        c is an ASCII character, code less than 0200

SEE ALSO
       ascii(7)



                               25 February 1983                       CTYPE(3)